That might be true, especially since the picture of the small fleet they had (and said that a typical tournament sized fleet would be roughly double of that) hat 4 cruisers/battleships and also 4 strike carriers.

EDIT: on the other hand, the 4th capital ship was a Beijing class which doesnt have that gap. So that leave this little fleet with 3 cruisers and 4 strike carriers which wouldnt match up if that really is for transportation the New Orleans class.

It may be that they are not physically attached to the parent ship, but rather follow them through the wormhole created by the parent's foldspace drive, much like in Halo 2 when In Amber Clad followed Solemn Penance through the slipspace portal it created in New Mombasa.

The ship could extend shields or subspace field (taking inspiration from all scifi here ) around the carrier to protect it in transit if necessary.

I cant imagine the UCM requiring their carriers docked for transit, as then some carriers may be lost if their parent ship is destroyed which doesn't really fit with the 'minimising casualties' ethos they have.

This way carriers can still escape as long as there is a capital ship remaining.

After drooling over the pics some more, I have noticed that there seems to be 3 types of railgun shown.

The New Orleans class has a small triple barrel version

The cruisers and battle ships either have triple barrel (on wing dorsal mounts) or double barrel (in ventral mounts) rail gun turrets. They are the same length and width, which to me implies the two barrel version has fewer, but more powerful shots.

Load outs:New Orleans 1 light 3 barrelParis class (is this the name of the basic cruiser?) 2 three barrel and 2 two barrelBerlin class 2 three barrel (and the MAC?)Moscow class 2 three barrel and 4 two barrelBerlin class 4 three barrel and 3 two barrel

Looking at the poster, the New Orleans Strike carrier has a foldspace drive, so I imagine it wouldn't need to nest with anything. And given as long as it's noded and accurate it seems a foldspace drive is capable of jumping a rather large distance, given in the piece of fluff, the lighter managed to escape from Saturn back to Niccolum (though suppose it could've been over several jumps).

For the railguns part of me assumes that given the turrets seem to be the same size, and the barrel lengths are roughly similar it's possibly something like the double barrelled turrets are using the same amount of power than the other turrets, but only using it on two barrels rather than three, which could mean more powerful magnets, so greater acceleration for the slug, thus greater energy being imparted on an opposing ship hull in a rather violent fashion.